Injection apparatus



INJECTION APPARATUS Filed Feb. 7, 1950 HTTUP/VEKS United States Patent INJECTION APPARATUS Albert E. Krug, Hawthorne, N. J., assignor to Becton,

Dickinson and Company, Rutherford, N. J., a corporation of New Jersey Application February 7, 1950, Serial No. 142,858

'10 Claims. (Cl. 128-218) This invention relates to a structurally and functionally improved hypodermic injection apparatus.

It is an object of the invention ot provide an improved mechanism of this nature and by means of which, with minimum effort, and with precise results, the epidermis and underlying tissues may be penetrated by a cannula, the desired solution or medicament may be injected and the cannula thereupon withdrawn.

A further object is that of furnishing an injection apparatus by means of which this sequence of operation may be accomplished through an improved automatically functioning mechanism, the operation of which need only be initiated by the attending physician or technician.

Another object is the design of a compact cartridge or ampule assembly which may be readily produced and discarded after a single use.

An additional object is that of providing a device of this type which will embrace relatively few parts, each individually simple and rugged in construction, such parts being capable of ready manufacture and assembly to furnish a unitary apparatus operating over long periods of time with freedom from all difiiculties and the parts of which apparatus may, when necessary, be cleaned with facility.

With these and other objects in mind reference is had to the attached sheet of drawings illustrating one practical embodiment of the invention and in which:

Fig. 1 is a sectional side view of the device and showing the parts of the same prior to operation; and

Fig. 2 is a similar view illustrating the positions assumed by the parts at one stage of their operation.

In these views the numeral indicates the casing of preferably tubular configuration, the upper or outer end of which is closed by a cap 11. The casing may be provided with a reduced lower portion in the form of an extension 12 defining a preferably cylindrical medicamentreceiving chamber bounded at its upper end by a flange '13. The lower end of the reduced portion is closed by a centrally perforated cap 14. The extension 12 and cap 14 may be coupled by coarse threads, or any other form of structure which will permit of the cap being readily detached or attached and which will retain that cap against the probability of accidental displacement.

These several parts-are conveniently formedof metal. Also the outer face of cap 14 constitutes a skin-contacting portion and to this end may be outwardly bulged, as at '15. Within the cap a conical spring 16 is provided, the purpose of which will be hereinafter brought out. This spring is preferably secured to the cap so as to be incapable of detachment therefrom. Above this spring and within the medicament chamber an ampule assembly is disposed.

This assembly conveniently includes a cartridge or tube 17 formed of glass or other suitable material. The rear end of this tube is closed by a piston stopper 18. Its forward end is closed by a stopper 19 which may be provided with a recess '20 in its inner face. The desired quantity of medicament is contained within the ampule '17 between the stoppers 18 and 19 to thus provide a medicament-containing ampule or chamber. Tube 17 is received within a sleeve 21 conveniently formed of aluminum and which adjacent its upper end is formed with a ridge 22extending from its outer face. Its lower end may be flared outwardly as indicated at 23. The diameter of the outwardly extending portion 23 and the rib or ridge 22 is suchthat the sleeveslidably fits within.

the bore of portion 12, and has bearing contact with the inner face of the latter. intermediate these points the sleeve presents a diameter such that it will not contact the face of this bore.

At a point short of its lower end the sleeve is provided with a transverse wall surface 24. This furnishes a rest or support for the outer face of stopper 19. Wall 24 is centrally perforated and has extending through it :a cannula 2:: which is secured against movement with respect to that wall. Both ends or the cannula are pointed and the inner end of the same has a length such that it may be extended through the diaphragm portion of the stopper 19 into the recess 20 of the latter to communicate with the body of medicament within the ampule body. With the parts in the position shown in big. 1, the length of the outer portion or the cannula is such that it extends to a point ust short or the outer face ot'cap 14. As will be apparent, spring 16 will normally maintain the ampule assembly in the elevated position shown in this figure. in line with ampule tube 11 the extended portion 12 may be formed with one or more sight apertures 26 providing windows through which the medicament cartridge may be viewed; the sleeve 21 being similarly furnished with sight openings 27.

As w ll be understood, the entire ampule assembly may be furnished as a sterilized unit.

ament-receiving chamber may readily be loaded or a spent ampule assembly may be removed therefrom. Additionally, those portions or the apparatus and especially the loading cap may easily be cleaned and sterilized.

in order to cause a pro ection or the cannula and ampule assembly and an e ection of medicament, a plunger 215 is provided to the rear of the medicament chamber. The diameter of this plunger is slightly less than the bore or the ampule tube 1). while various sources or power may be employed to project and retract plunger 26 it is preierred, according to the present teachings, to utilize electricity. 'lhereiore, plunger 26 is connected to an armature 29 and may be integral therewith. 'lhis armature is normally maintained in retracted position by a spring An electro-magnet 31 is disposed within casing 10 in operative relationship with respect to armature 29. A control such as a switch 32. is connected to the windings or the eiectro-inagnet and a source o1 current supply. 11118 switch is prererably of a type which when once actuated will remain closed for a desired interval or time (tor example, one to two seconds). A shoulder 33 may deline the point of juncture between plunger 28 and armature 29. The diameter orthis shoulder is such that it may engage stop 34 and the length of plunger 28 is such that it may bring stopper 18 into engagement with the inner face of stopper 19.

With the parts assembled as shown in Fig. 1, the cannula bore will be tilled with liquid and the end face of cap 14 may be brought to overlie the patients skin at a point at which the nijection is to be made. Thereupon by actuating the control 32 the circuit electro magnet 31 will be closed and armature 29 will be pro ected in a rapid manner. Incident to such proection plunger 28 will engage stopper 18 and due to the incompressibility of the liquid within ampule 17, the latter will be projected against the action of spring 16 and will carry with it cannula 25.

The cannula should ordinarily not be less than 26 gauge. It will penetrate the epidermis and tissues underlying the same until the parts have reached the position shown in Fig. 2. In that position, spring 16 will be compressed and further inward movement of the ampule assembly will be arrested. During this functioning of the parts very little, if any, medicament will be lost .due to the small escape orifice furnished by the bore through be projected within the ampule. medrcament being forced through the bore of the needle and into the tissues adjacent the point of extreme penewill penetrate stopper 19. The apparatus is now ready -for re-use.

of the cannula and the rapidity with which the projectron occurs. The outer needle end will have penetrated the tissues. Under continued energization of the electromagnet, plunger 28 will now cause piston stopper 13 to This will result in tration of the latter by the needle. This action will con- .'tinue until substantially all solution within the ampule has been discharged. At that time, either by release of .the control 32 or due to the expiration of the time interval during which it remains automatically closed, the

-electro-magnet will be de'energized.

With such de-energization, spring 30 will retract arma- .ture 29. Likewise spring 16 will retract the sleeve 21, needle 25 and ampule 17. Thus, the cannula will be .rapidly withdrawn from the flesh of the patient. scrdent to the rapid penetration and wtihdrawal actions 0f the cannula, no pain will be experienced by the patient .or at worst the level of pain will be materially reduced. Ihe physician may reassure himself that all medicament is properly discharged by observing the position of stopper .18 within the ampule 17 through windows 26 and 27 if the latter are provided.

As afore described, cap 14 may now be dismounted and the ampule assembly discarded. The cannula and sleeve may be disposed within a sterilizer. A new ampule may be positioned within the apparatus and a steri- With As will be understood, the depth to which the needle penetrates is contingent upon the length of j, the latter and the proportioning of the parts of the apparatus.

-, Thus, among others, the several objects of the invention as specifically aforenoted are achieved. Obviously .numerous changes in construction and rearrangement of the parts might be resorted to without departing from the .spirit of the invention as defined by the claims. I claim:

1. In an injection apparatus in which a hollow needle is to be automatically projected to pierce the epidermis and in which thereafter fluid is to be automatically injected into the underlying tissues, 21 body formed with a chamber, an apertured end member attached to said ..body, a power driven plunger mounted for reciprocation within said body and projectible into said chamber, said chamber presenting surfaces to slidably support an ampule and needle assembly, said chamber having an overall length and said plunger having a length of travel :such that said assembly may be accommodated Within said chamber with the needle housed within said body said needle passing through the aperture in said end 'member and beyond the same, said plunger in the final stages of its stroke functioning to expel medicament from within the ampule contained in said chamber and through the hollow bore of said needle.

2. An in ection apparatus including in combination a body formed with a medicament receiving chamber, a

plunger projectible into said chamber, means for so proectmg said plunger, an apertured end member connected to said body, an ampule supporting member disposed within said chamber in movable relationship with respect to the walls of the same and a needle carried by said ampule supporting member and projectible through said aperture.

" 3. An injection apparatus including in combination a 'body formed with a medicament receiving chamber, a plunger pro ectlble into said chamber, means for so projecting said plunger, an apertured end member connected 'to said body, an ampule supporting member disposed .within said chamber in movable relationship with respect lto the walls of the same, a needle carried by said ampule supporting member and projectible through said aperture and means interposed between said end member and 'ampule supporting member for normally urging the latter ..and the needle carried thereby into retracted position ..within said chamber.

4. In an injection apparatus an assembly including in combination a sleeve, surfaces forming a part of said -sleeve to support an ampule, a double ended hollow needle, said needle being affixed against movement with respect to said sleeve and bearing surfaces having reduced contact areas forming a part of said sleeve and extending outwardly therefrom to slidably engage the faces of a main injection apparatus.

5. An injection apparatus including in combination a casing, a plunger projectible under power within said casing, a support for a medicament chamber movably mounted within said casing, an apertured end member secured to said casing, a needle afiixed to said support and projectible through said aperture, a spring interposed between said support and end member to normally maintain the latter in retracted position and means for guiding plunger in its projection whereby it will move in telescopic relationship with respect to said support.

6. An injection apparatus including in combination a casing, a plunger projectible under power within said casing, a support for a medicament chamber movably mounted within said casing, an apertured end member secured to said casing, a needle aifixed to said support and projectible through said aperture, a spring interposed between said support and end member to normally maintain the latter in retracted position, means for guiding said plunger in its projection whereby it will move in telescopic relationship with respect to said support, a power source mounted by said casing and acting upon said plunger and a spring connected to said plunger and normally tending to retract the latter.

7. A hypodermic injection apparatus including in combination a casing formed with a chamber, a supporting sleeve slidable within said chamber and provided with a bore to receive an ampule, a power plunger carri=- by said casing and projectible into the bore of said sleeve, an end member for said chamber provided with an opening and means interposed between said member and sleeve to normally maintain the latter at a position remote from said member.

8. An injection apparatus including in combination a casing, an electro-rnagnet associated with said casing, an armature movable with respect to said magnet and disposed in operative relationship thereto, a plunger connected to move with said armature, a hollow ampule element, a piston carried by and movable with respect to said element, a hollow needle also carried by said element and movable with the same, and said casing being formed with a chamber, said element being slidably mounted within said chamber to have its piston en aged by said plunger and said chamber being formed with an opening through which said needle is projected as said element slides within said chamber.

9. In a hypodermic injection apparatus in combination a body formed with a medicament chamber, an ampule apertured end member attached to said body, an element to contain medicament and slidably mounted in said chamber, a hollow needle supported by said element and with the latter in retracted position within said chamber-being enclosed within said apparatus, a power-driven plunger mounted for reciprocation within said body and projectible into said chamber and said plunger being engagable with said element and having a length of travel equal to that necessary to project the element and needle to a point where the latter extends beyond the body a distance equal to that necessary to efiect the desired depth of tissue-penetration plus a distance such that the medicament within the element will be expelled therefrom through said needle.

10. In a hypodermic injection apparatus in combination a body formed with a medicament chamber, an apertured end member attached to said body, an ampule element to contain medicament and slidably mounted in said chamber, a hollow needle supported by said element and with the latter in retracted position within said chamber-being enclosed within said apparatus, a power-driven plunger mounted for reciprocation within said body and projectible into said chamber, said plunger being engageable with said element and having a leng h of travel equal to that necessary to project the element and needle to a point where the latter extends beyond the body a distance equal to that necessary to efiect the desired depth of tissue-penetration plus a distance such that the medicament within the element will be expelled therefrom through said needle and means for normally maintaining said element and plunger in retracted position whereby the needle is likewise normally maintained, housed within said body.

(References on following page) References Cited in the file of this patent UNITED STATES PATENTS Quayle May 27, 1924 Marcy Mar. 17, 1928 5 Kulik Dec. 3, 1929 Hoskins Feb. 18, 1930 6 Smith July 15, 1930 Perrin Oct. 11, 1932 Hein Oct. 3, 1933 Hansen May 24, 1938 Strobell Nov. 5, 1946 Maynes June 7, 1949 

